Lifting-jack.



PATENTED APR 4;, 1905.

No. 78 L712.

J. T. ARGO LIPTIBIG- JACK.

APPLICATION I LED JUHE 16 1904 inventor Patented April 4, 1905.

PATENT OFFICE.

iLOHN T. ARGO, OF CYNTHIANA, KENTUCKY.

LIFTiNGl dACK- SPECIFICATION forming part of Letters Patent No. 786,712, dated April 4, 1905.

Application filed June 16,1904. Serial No. 212,811.

To a whom. it may concern:

Be it known that I, JOHN T. Aneo, a citizen of the United States, residing at Cynthiana, in the county of Harrison and State of Kentucky, have invented certain new and useful Improvements in Lifting-Jacks, of which the following is a specification.

This invention provides improvements in that class of devices commonly called lifting-jacks, being specially adapted for use as a carriage-jack; and the principal feature of the invention rests in the provision of a device of this type embodying an extreme simplicity as regards the number of operative parts employed and as regards theoperation and arrangement of said parts.

For a full description of the invention and the merits thereof and also to acquire a knowledge of the details of construction of the means for effecting the result reference is to be had to the following description and accompanying drawings.

\Vhile the essential and characteristic features of the invention are susceptible of modification, still the preferred embodiment of the invention is illustrated in the accompanying drawings, in which Figure 1 isa perspective view of a jack constructed in accordance with my invention. Fig. 2 is a side elevation.

Corresponding and like parts are referred to in the following description and indicated in both views of the drawings by the same reference characters.

The jack comprises, essentially, the base 1, a lifting-head 2,moun ted upon the base 1,a supporting-bar 3, and a lever t, cooperating with the lifting-head and the supporting-bar to effect the necessary operation of the device.

An advantageous structural feature of my invention resides in the general cheapness of the operating parts, whereby same are assembled so as to occupy a minimum amount of space when the jack is not in use, at the same time being adapted to give a maximum amount of power with reference to the lifting qualities thereof.

Projecting upwardly from the base 1 and about centrally thereof is a su1' p0rtingstand ard 5, and guide-straps 6 project laterally from the snpportirig-standard 5, so as to receive therein a guide-bar 7, which extends downwardly from the lifting-head 2. The guidebar 7 of the lifting-head 2 is vertically movable relative to the standard of the base 1, and its movement is such as to give the necessary lift to the head 2 in the operation of the device.

The head 2 is of usual formation generally, being stepped at intervals, as shown at 8.

The supporting-bar 3 is pivoted at its lower end, as shown at 9, and is disposed upon that side of the standard 5 opposite to which the guide-bar 7 operates.

The lever 4 is of special formation, being provided at its lower end with lateral pivot extensions 10, said extensions extending in opposite directions, one being pivotally connected with the head 2 and the other with the upper end of the supporting-bar 3. The pivot extensions 10 of the lever 4 are preferably of integral formation therewith, and said extensions constitute knuckles of approximately circular formation, the extension which is pivoted to the head 2 is received in an approximately circular recess 11 in the side of the head. The other extension, 10, which is pivotally secured to the bar 3, is received by a round recess portion in the upper end of this bar and is thus freely movable thereon. The extension 10, connected with the bar 3, is adapted to be received in a curved recess 12, disposed below and adjacent to the recess 11 in the head when the head is elevated in a lift ing operation.

The point of pivotal connection of the bar 3 with the lever 4 is designed to move in rear of the fulcrum-point of the lever upon the head 2 when the leverd is thrown downwardly to elevate the head, and the disposition of the pivotal connection of the lever with the bar 3 will thus be such as to hold the lever locked in its lowermost disposition, above described. In providing the extensions 10 of the special formation indicated the same will snugly lit against the head 2 and the supporting-bar 3 Will also rest ngai net the stznidnrd 5 of the base, all affording a. iDDiDQilSi) and extremely rigid construe-thin.

Having thus described the invention, what is claimed as new is 1. In a. liftinpfiaeh, the combination of a base, a. movable need, a supporting-bar pivoted at its lower end to the base, a lever provided at its lower end with integral pivotal extensions of approximately circular torinw tion projected laterally therefrom in opposite directions, the head being provided with a circular seat or recess receiving one of the extensions of the lever, and pivotal connections between the extensions of the lever and the supporting-lmr and head.

2. in a lifting fe a', the combination of a base, a support-i standard projected upwa dly from the lane, guide-straps extended lronii the SlIIP'QCiU standard, a guide-bin mounted in said sir 1., it lifting-heed carried by the upper end of the guide-her, a supporting-bar pivoted at its lower end to the base, a. lever provided at its lower end with oppositely-projected pivotal extensions of circular formation, the head being provided with a circular seat or recess 11 receiving one of tire tensions of the lever and having pivotal connection therewith, the other extension of the lever being pivotally connected with the upper end of the supporting-bar, the supporting-bar being provided with it curved recess to receive the lest-mentioned extension of the lever, the head being provided with the curved recess 1'2 receiving the lest-mentioned exten sion when the lever is thrown downwardly.

in testimony whereof I itfiiX my signature in presence of tWo witnesses.

JOHN Ti. ARGO. [n s] \Vitnesscs:

H. K. TAYLOR, U. H. Cox. 

